In the work
Max Binary Fibonacci Reps Density no. 6,
I tried to put some of the most interesting things I learned in a course on electroacoustic music to use. Two of the most striking
things I learned about were 1) the ability to simulate the natural phenomenon
of delay through electroacoustic means and 2) the
possibility to make things seem to come from more in the distance using
filtering of the higher frequencies, in turn, imitating the natural phenomenon
that higher pitches lose intensity faster than lower pitches through air.

Compositional Process

When I went
to write this work, I had already experimented with delay in Csound, which has a simple opcode
named delay with the following syntax: asig delayainput, adeltime. I found it fascinating how I could make it seem like the sound was
coming from the extreme edges of the speakers – or perhaps even beyond – by using
a .007 second delay between the left and right speakers.

In my
original experiments I used the same amplitude for both speakers, simulating
space using only delays. I found, however, that a more realistic and pleasing
result could be achieved by using a mild mix of panning and delay. This is due
to the fact that reflections are generally quieter than direct signals. As a
sound I used a .33 liter bottle flicked with the
fingernail. I recorded the sound in my studio, in which the walls are
completely covered with acoustic foam. I chose this sound, because I new that a
bottle being struck is a sound that is easy to localize. This is primarily due
to the high pitches and extremely crisp attack produced. Although the signal
was recorded at a high amplitude, I chose to use a
quieter amplitude in the actual compositions to make the sound seem slightly
more distant and tame. After this experiment I wrote Phi Signature Sequence no. 16 using the instrument I had created.

After
writing another extremely brief work entitled Horizontal Para-Fibonacci Sequence no. 21 using the same instrument
with a different sample, I began work on Max
Binary Fibonacci Reps Density no. 6 by building a low pass filter into the
instrument I had used before and creating a parameter for dry-wet mix. For this
work I used a .5 liter bottle struck with a metal
fork and recorded it in my bathroom which has a large amount of reverb, as it
is practically all tile and flat reflective surfaces. This environment softened
the attack a tad, but did not have an extremely dramatic effect on the outcome,
as I only was interested in using the first .057 seconds of the attack anyway.
The sound was incidentally recorded using one Neumann KM 183, an
omni-directional condenser microphone.

My goal was
then to make it seem as if the sound started at the extreme right corner and
moved backward into the distance at the same time as moving left creating a
diagonal as the pitch fell as shown in the following diagram:

As
explained earlier, the idea was to create the illusion of distance by using a
low-pass filter to slowly roll off the higher frequencies. At the same time, the
delay and pan effect would create the movement from right to left. In addition
to rolling off the higher frequencies, the loudness of the signal was also
decreased from right to left.

This is the
Csound instrument I used in this piece:

instr 1

krandrand2, 2

iamp = i(krand)

kenvlinenp5+iamp, 0, p3, p4

aosclposcil3kenv, p6/3249.5,5472,5472,1

abrbutterlpaosc, p10

awdsumabr*(p9), aosc*(1-p9)

if (p8==0) goto mid

kenvdlinseg1, p3-abs(p8)-p4, 1, p4, 0

adeldelayawd*kenvd, abs(p8)

if (p8<0) goto left

goto right

left:

outsawd*p7, adel*(1-p7)

goto end

mid:

outsawd*p7, awd*(1-p7)

goto end

right:

outsadel*p7, awd*(1-p7)

end:

endin

It uses a
simple linear envelope whose amplitude is given by parameter 5 in the score (p5). In the piece I used the natural
attack of the bottle, but used a short .008 release at the end of each .057
second tone. The opcoderand feeds a random float between 0 and 2 to the envelope, a sort of
“humanizing” effect. This way if the same note is played two times, the signal
is not exactly identical (although extremely close since I am only adding a
maximum of 2). I made the randopcode seeded by the system clock, so that every rendering
of the piece would be different as well. lposcil3 is a looping oscillator with high
precision and cubic interpolation. I do not use this oscillator to loop, but
rather to play a sample back which is written into a table with a GEN function
like such:

f1 0 0 1 "bottle_ping_in_bathroom_trunc.wav" 0 00

I then use lposcil3to play
backthe sample at different rates
of speed; the original truncated recording is 5472 samples long in 24-bit 96kHz (.057 seconds). The approximate pitch is given by p6in the
score. I use the low-pass filter opcodebutterlptofilter the signal leaving the cut-off
frequency to p10in the
score, in the piece it is slowly rolled down from 24,000 Hz to 3,125 Hz as the
wet-dry mix – created here using sum – is
also increased somewhat exponentially from .01 to .99 ( with 1 being a fully
filtered signal). The cut-off, delay, pan and amplitude were all adjusted
individually for each note. A separate envelope was created to compensate for
the shorter duration of the delayed notes, this was
accomplished using a linseg. I made it possible for the delayopcode to
accept negative values; in this composition I made it so that positive numbers indicate
that the sound is coming from the right side with negative coming from left. To
accomplish this I used ifstatements and goto calls. In the end the instrument took the
following arguments:

;instr start durrel amp
cps L decwetdrycutoff

;example:

i1 0 .057 .008 $a1 3028.000 $l1 $d1 $w1 $c1

The $ signs
represent macros I used as a shorthand for the score.

Results, Conclusions

In the end,
the effect I had set out to achieve was reached to a satisfactory point.
Perhaps in retrospect I should have rolled the amplitude back
a bit more with the filter cut-off. I think through more experimentation and
better tools (computer programs created for this purpose) it will be possible
to achieve more refined results in the future. I think that the careful balance
of all parameters is extremely important in producing a convincing effect;
wet-dry mix, cut-off frequency, amplitude, delay and panning.

One might
ask, how does this serve your music, seeing as you
compose with Fibonacci numbers? To that I would say that these techniques
provide a sharper level of clarity in the stereo projection of sound elements
in space, which makes it possible to create clearer, more comprehensible
musical structures in stereo or multi-channel. I see great possibilities in
these techniques for my music in the future.